Multiple fuse



July 2, 1940- w. c. LINTON '2,26,785

I MULTIPLE FUSE Y Filed March 6, 1939 2 Sheets-Sheet l [I5/APH 25 Vo f5 l. n

i I @Si 5 .4 4 Y' -z W. C. LINTON July 2, 1940.

MULTIPLE FUSE 2 Sheets-Sheet 2 Filed March 6, 1939 Patented July 2, 1940 MULTIPLE FUSE William C. Linton. Washington, D. C., asslgnor to Fuse Indicator (krporation, Washinxto D. C., a corporation of Delaware Application March 8, 1939, Serial No. 280,180

4 Claims (Cl. 20o-121) The present invention relates to multiple fuses of the plug type having means for visibly indicating the ruptured or blown condition oi the thermal elements thereof, all of which are confined in a single unitary structure. The conventional type of multiple plug fuses have arranged therein a plurality oi fuse links and a rotatable member which selectively and in succession causes the fuse linlrs to be connected in series with the Contact terminals oi the fuse plug as they come blown or ruptured by short circuiting or overloading ie electrical circuit in which the plug connected. To the Contact terminals oi this type oi' multiple fuse plugs is connected a s'nunt circuit having e glow lamp and leak resistor included therein, which latter are arranged in series with the contact terminals of the fuse plug but to the fuse links, which latter are also connected in series to the contact terminals ci the :luce plug, whereby, when a fuse slows or becomes runtured, the glow lamp will be to give oli or emit a visible signal, indicating tneinoperative condition of such fuse linlr. By turning the rotatable member, a new 'use lint: will be connected to the contact terminais ol the fuse plug, thereby again completing the electrical circuit and as no current will pass to the glow lamp, the latter will again be extinguished. Movable contacts must necessarily be carried by the rotatable member, whereby the iuse links and shunt circuit having the glow lamp arranged therein may be selectively connected to the contact terminals oi the fuse plug and it ls an object of the present invention to provide a new and' novel manner of mounting a glow lamp, resistor and connections therefor upon such rotatable members, whereby, the several parts thereof may be easily and readily assembled for materially decreasing the cost associated with the manufacture of such multiple indicating fuse plugs and, at the same time, eect a positive connection between the movable contacts and the contact terminals of the fuse as well as safeguarding the fuse links and the movable contacts irom becoming damaged or rendered inoperative by eliminating all possible chances oi the molten metal coming in contact therewith which is given oil by the blowing or melting of a fuse link when a short circuit occurs.

Other objects ofthe invention will be in part obvious and in part pointed out hereinafter.

In order that the invention and its mode oi operation may be readily understood by persons skilled in the art, I have in the accompanying drawings and 'in the detailed `following descriptrated a conventional type of multiple inse plug tion based thereupon, set out an embodiment ofv the same.

In the drawings:

Fig. 1 is a top plan view of a multiple inse embodying the present invention. El

Fig. 2 is a top plan View of the casing ot the fuse plug with the signal lamp and its cover cemoved.

Fig. E is a vertical transverse sectional view through the completed imc folug.

Fig. t is a vertical transverse sectional 'view ci the fuse plus tetten at right angles to 3.

Fie. 5 is a horizontal section, teiten on line 5--5 ci Fig. 3 in the direction oi' the arrow points.

Fig. o is a horizontal section taken on the line -E of Fig. i in the direction oi the arrow pointe.

Fig. 7 is e side elevation of the connector bloeit.

Fig. 8 is a detail vertical section through the rotatable member or core.

Fig. 9 is a clan view of the disc eene-rotor or 2o partition. v

Fig. l0 is a detail perspective view of one of the i'use links.

Fig. 1l is a vertical section thi-ouah a inse plug showing a slightly modified form oi the invention.

Fig. l2 is a horizontal section taken on the line I2-I2 oi Fig. l1 in the direction of the arrow points.

Fig. 13 is an enlarged detail section, and

Fig. .l-i is a plan view of a ilbervwasner constitutinc an element of the fuse plug.

Referring now more particularly to `Figs. l to 1c inclusive of the drawings wherein l have illushaving a, glow lamp indicator attached thereto, which comprises a tubular casing i molded from suitable insulating material and having a central tapered. bore extending entirely therethrough.

Fitted within this bore of the casing i is a ro- 4@ tatable member or core t and which core is retained within the casing i by means of a cap or base 3. A standard threaded contact shell t connects the base 3 to the casing i and has e. polygonal opening formed. therein which receives e. coru respondlngly shaped boss 5 formeel with the base 3, which prevents the latter from rotating with respect to the casing i. The inner ieee of the base 3 is provided with an upstanding conicalshaped boss t and the casing i, core 2 and base 3 are preferably molded from suitable insulating materials. The upper end of the core 2 is provided with a pocket 1 preferably of a square configuration in whichis seated a lug 8 formed with the lower face of a block 9 in order that when the upper end of the core 38 is in the form of a circular disc which covers the upper ends of the core and the casing 36.

A central contact member 48 is in the form of a metallic rivet and extends through the casing, core and block 41 and by means of the soldered connection 49, retains the core within the' casing 3B as well as the block thereupon.

Seated upon a boss formed within the casing 3B is a contact member 50 and this latter has rotatable engagement with the shank portion of the rivet 48. This Contact member 50 being semispherical, provides a lower bearing for the core 33 as well as a more positive connection between the hub portion 4i of the fuse links and the central contact or rivet 48.

The glow lamp 5| is seated upon the block 41 and has one lead wire 52 connected to the rivet 48 by means of the solder 49, Whereas the other lead wire 53 has its outer extremity embedded within a plastic leak resistor 54. This resistor 54 is seated within a pocket or recess formed within thexblock 41 and is also electrically connected to the ring 44 by means of a pin or other conductor l5.

Formed with the block 41 and extending from the upper face thereof are the flanges or ribs 58, which latter have a snap-on connection with the cover 51 and this cover not only houses the lamp 5I but provides a handhold for turning the core 38, whereby the fuse links may be selectively brought into4 engagement with the terminals 43 of the spring contact.

During the normal operation of this fuse plug, the current will flow from the shell 31 through the spring contact 42, through a ruse link to the central contact 43 but should this latter fuse link become blown or ruptured, the current will ilow from the spring contact 42 through that remaining portion or the upper end of the blown fuse link to the ring 44, through the leak reslstor 54 to the lamp 5I and then return through the central contact 43, thereby causing the lamp to glow for giving of! a visible sig'nal as to the blown or ruptured condition of the fuse link. By turning the core 36, a new or good fuse link 40 will be brought into engagement with the spring contact 43 for again causing the current to flow therethrough and as no current will pass to the lamp 5I, the latter will again be extinguished.

From the foregoing, it will be apparent that I have established a new and novel manner of mounting a lamp indicator upon the rotatable member of a conventional multiple plug type Iuse as well as mounting movable contacts and other elements of the electrical circuit in which the lamp is included upon such rotatable member, whereby the several parts thereof may be more readily and easily assembled, thereby materially reducing the cost associated with the manufacture of such indicating fuses of the multiple plug type. l

Manifestly, the construction herein shown is capable of considerable modlcation and such modiiications as come within the scope of my claims, I consider within the spirit of my invention.

I claim: y

l. A multiple fuse plug comprising a body formed with a chamber open at its upper end and having its annular wall formed with a side opening, an internal annular ledge being formed adjacent the open end oi the body, a boss projecting inwardly from the lower end of said body into said chamber, a stationary contact in said chamber having a shank extending longitudinal- I lyof the body and passing outwardly through the side opening thereof, a shell terminal fitting about said body and engaging the outer portion of the shank of said contact, a rotatable core in said body, a bearing of conductive material between the inner end of said core and the end of said boss, a fuse having a hub disposed betweeny the core and said bearing and arms extending from the hub longitudinally of the core in spaced relation to each other circumferentially of the core for successive engagement by the stationary contact when the corey is turned to'adjusted positions, a flange about the outer end of said core, a ring of conductive materialfitting about said core against said flange and engaged by outer ends of the fuse arms, a washer of insulating material iitting upon said ledge and engaged by said ring with a portion for spacing said ring from said stationary contact, a cap for the upper end of said body having a boss extending therefrom and seated in a recess formed in the outer end of the core for turning engagement therewith,

a center terminal rivet passing through the core and bearing with its end portions extending through the cap and the lower endof the body and headed to hold the bearing Yand the core and the cap in place, said cap being formed with a socket and the flange of the core with an opening between the socket and the conductive ring, a plastic leak resistor composition in said pocket, means extending through the opening of the ,flange for connecting said conductive ring with said composition, a signal lamp having a conductor connected to one end of said rivet and a second conductor connected with the composition, and casing of light penetratable material carried by said cap in enclosing relation to the signal lamp and serving asmeans for imparting turning adjustment to the cap and the core.

2. A multiple indicating fuse comprising a casing, a rotatable core arranged within said casing and having a chamber formed therein, a central contact connected to said rotatable core, a threaded shell contact connected to said casing, a spring contact member connected to said central contact, a' plurality of fuse links arranged within said casing whereby said spring contact may selectively engage said fuse links, a glow lamp indicator carried by said rotatable core having one lead wire thereof connected to said central contact, said rotatable core having a pocket formed therein, a spring actuated ball contact arranged within the pocket of said core and adapted to selectively engage said fuse links and a leak resistor connecting said ball contact with the other lead wire of said lamp.

3. A multiple plug fuse comprising an outer casing, al rotatable core arranged within said casing and having an explosive chamber i'ormed therein, a boss formed with scid outer casing and extending vertically within the explosive chamber lof said core, a central contact extending through said boss and connected to said rotatable core, a threaded contact shell carried by said caslng, a plurality of fuse links, a partition seated upon said boss for dividing said explosive chamber into separate sections, a spring contact member arranged within one of the sections of said explosive chamber and connected to said central contact whereby with therotation of said core, said spring contact may selectively engage one end of each of said fuse links and means for electrically connecting the opposite ends of said fuse links to said threaded contact shell. 

